The liquidity and expiry availability in this underlying turned out to be "not that hot" when I looked at it during the NY session. Currently, for example, there is no June monthly; I'd like a September, but there isn't one; I'd have to go out to November for the back month, and the bid/ask ... ewwwww. The Nov 16th 18 long/June 1st 20.5 short is bid 0.00/ask .37/mid .19 ... . Looked good on paper.